Welding electrode holder



April 10, 1945.

w. B. SHELLABARGER 2,373,605

WELDING ELECTRODE HOLDER Filed May 5, 1944 INV NTR Patented Apr. 10, 1945 UNITED STATES PATENT OFFICE 4 Claims.

This invention relates to electrode holders wherein a weld-wire is engaged by spring closing jaws operating as tongs, and has for its object to provide a simplified construction which will have high safety characteristics especially any possibility of arcing between the body, the laws, or the handle of the holder and any structure with which such parts may be brought into contact.

It has been the general practice to make both of the holding Jaws of an electrode holder live as to their electrical contact with the welding wire, and consequently special insulating means have been called for not only around the fixed jaw and its connections but about the movable jaw, its handle and other metal attachments. Such insulation tends toward an unnecessarily clumsy and bulky device, with added weight, and is often not completely protective to the most desirable extent. To offset the resulting possibilities of dangerous arcing between the holder and surrounding structure various types of switches have sometimes been incorporated in such holders to render the frame dead when the welding wire is removed, but such switches still leave the frame of the handle members live when the wire is in position.

The present invention, therefore, contemplates the provision of a single contact electrode holder in which the contact is in the fixed jaw and detachably connected to an insulated conductor, the movable jaw having a facing of insulating material closing on said contact, and said contact being surrounded by insulating walls terminating substantially flush with the operating surface of said contact.

Still further objects and advantages additional or subsidiary to the aforesaid objects, or resulting from the construction or operation of the invention as it may be carried into effect, will become apparent a the said invention is hereinafter further disclosed.

In carrying the said invention into effect, I may adopt the novel construction and arrangement of parts hereinafter described and ascertained having reference to the example illustrated in the accompanying drawing, wherein:

Figure 1 is an elevation partly shown in section of the operative end portion of an electrode holder embodying the said invention;

Figure 2 is plan view of the lower contactcarrying jaw; and

Figure 3 is a. cross section taken on a plane indicated by the line 3-3 in Figure 1.

Similar characters of reference indicate similar parts in the several figures of the drawing. The tubular body portion ii! of the holder has an upper opening in the front end in which is located the contact block which in the illustration is provided with a tapered hole l2 to receive the correspondingly tapered end |3 of the conductor H. I prefer to make this tapered connection of such slight angle that it will afford a firm self-securing engagement between the block and the conductor such as will resist loosening or disengagement from normal use of the device but will permit such disengagement by a deliberately applied force for disassembling when desired.

The said contact block ll extends above the upper surface of the tubular body in and is of smaller dimensions in length and width than the said opening, whereby it may be surrounded by insulating wall members i5, i6, ll and i8 spacing the said block from the side and end walls of the body. These insulating wall members extend upwardly around the block H to substantially the level of the upper working surface of the said contact block, so that only such surface is exposed.

The outer side walls of the said members l5, Ni, ii and it may be grooved at i9, 20, El and 22 so that the marginal edges of the body portion it may enter into engagement therewith to assist in holding the said insulating members in assembled position as will be readily understood. 23 is an insulating plate or liner extending beneath the said block ll. Where the insulating wall i6 extends below the level of the conductor II it may have a suitable opening therein through which the said conductor passes. 24 indicates the tubular insulating liner between the conductor II and the outer body casing Ill.

The upper jaw 25, which is extended rearwardly in the form of the lever 28, is faced with a pad of insulating material 21, shown as being carried by an inverted tray-like frame 28, suitably attached to the movable jaw 25, and I prefer to make this insulating pad 21 conform in dimensions with the outline of the surrounding upper edges of the insulating walls l5, l6, l1 and 18 so that, when the Jaw is closed this pad will not only completely cover the upper surface of the contact block II, but will extend over the upper edges of the surrounding insulating walls. The edges of the carrier 28 are preferably recessed into the edges of the insulating pad 21, and it will u be obvious that any of the said insulating walls l5, l8, l1 and I8, or the insulating pad 21, may be removed and replaced it thought necessary or desirable, such as when they may have become unduly worn after long usage.

From the foregoing it will be readily seen that a minimum surface, that is merely the upper face of the contact block I I, is exposed as a live" surface at any time, thegmovable jaw being at all times entirely a dead member, and even this upper surface of the contact block H is thoroughly concealed and insulated from all possibility of contact when the jaws are closed.

The arrangement described permits of the very simplest construction as to manufacture, assembly, and use, with a very high degree of safety This invention may be developed within the scope of the following claims without departing from the essential features of the said invention, and it is desired that the specification and drawing be read as being merely illustrative of a practical form of device and not in a strictly limiting sense.

What I claim is:

1. In a device of the class described, a movable jaw member, a fixed jaw member, a contact block in and insulated from said fixed member, said block extending upwardly therefrom to present a contact face toward said movable member, insulating side walls surrounding said block, and an insulating pad on the face of said movable member extending completely over the face of said block when said movable member is closed thereon.

2. In a device of the class described, a movable jaw member, a fixed jaw member, a contact block in and extending from said fixed member, said block extending upwardly therefrom to l present a contact face toward said movable member, insulating side walls surrounding and terminating fiush with the face of said block, and an insulating pad on the face of said movable member extending completely over the face of said block and the upper edges of said insulating side walls when said movable member is closed thereon.

3. In a device of the class described, a movable jaw member, a fixed jaw member, a contact block in and insulated from said fixed member, said block extending upwardly therefrom to present a contact face toward said movable member, detachably replaceable insulating side walls surrounding said block, and an insulating pad on the face of said movable member extending completely over the face of said block when said movable member is closed thereon.

4. In a device of the class described, a movable jaw member, a fixed jaw member, a contact block in and insulated from said fixed member, said block extending upwardly therefrom to present a contact face toward said movable member, detachably replaceable insulating side walls surrounding said block, and a detachable and replaceable insulating pad on the face of said movable member extending completely over the face of said block when said movable member is closed thereon. WILLIAM B. SHELLABARGER. 

